Liming Zhang,  A New Time-Frequency Speech Analysis Approach Based On Adaptive Fourier Decomposition.   journal   = {International Journal of Electrical and Computer Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2013, vol. 79(7). 938 - 942
    [viewed 13 July 2020]. Available from: https://publications.waset.org/pdf/16525.